Do you realize that we are all rising the hashrate, rising the diff, and then earning the same as before??
It's been said many times before, but we're also drowning out the CPUs aka botnets by making GPUs more faster.
It's squeezing out more and more miners since this is for a very specific build (windows, 64 bit, newer AMD cards). Not only that, it is making a few specific card models more profitable since each new version is raising the high hash card by more sol/s then the low hash cards. Incrementally a very specific mining machine build is becoming more profitable at the expense of other builds.